perf evsel: Record fd into perf_mmap
Add a fd field into struct perf_mmap so that perf can track the mmap fd.
This feature will be used for toggling overwrite ring buffers.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1463762315-155689-3-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index c4bfe11..1a370db 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -881,6 +881,7 @@
if (evlist->mmap[idx].base != NULL) {
munmap(evlist->mmap[idx].base, evlist->mmap_len);
evlist->mmap[idx].base = NULL;
+ evlist->mmap[idx].fd = -1;
atomic_set(&evlist->mmap[idx].refcnt, 0);
}
auxtrace_mmap__munmap(&evlist->mmap[idx].auxtrace_mmap);
@@ -901,10 +902,14 @@
static int perf_evlist__alloc_mmap(struct perf_evlist *evlist)
{
+ int i;
+
evlist->nr_mmaps = cpu_map__nr(evlist->cpus);
if (cpu_map__empty(evlist->cpus))
evlist->nr_mmaps = thread_map__nr(evlist->threads);
evlist->mmap = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap));
+ for (i = 0; i < evlist->nr_mmaps; i++)
+ evlist->mmap[i].fd = -1;
return evlist->mmap != NULL ? 0 : -ENOMEM;
}
@@ -941,6 +946,7 @@
evlist->mmap[idx].base = NULL;
return -1;
}
+ evlist->mmap[idx].fd = fd;
if (auxtrace_mmap__mmap(&evlist->mmap[idx].auxtrace_mmap,
&mp->auxtrace_mp, evlist->mmap[idx].base, fd))
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 85d1b598..0d165b1 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -28,6 +28,7 @@
struct perf_mmap {
void *base;
int mask;
+ int fd;
atomic_t refcnt;
u64 prev;
struct auxtrace_mmap auxtrace_mmap;